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A syndrome of peripheral polyneuropathy associated with islet cell tumors and hypoglycemia has been reported in 28 patients. Despite varying features in these patients, the clinical characteristics of this syndrome are remarkably similar. These consist of the development of a sensorimotor neuropathy during a protracted course of recurrent severe hypoglycemia, related to underlying insulinoma. Cerebral symptoms dominate the clinical picture and a predominantly or entirely motor, distal and symmetric, peripheral neuropathy ensures. Upper limb involvement is more frequent, accompanied by severe weakness and distal wasting, usually without fasciculations. Painful distal paresthesias without objective sensory loss are characteristic. Direct relationship to a single hypoglycemic insult is often absent. This report describes the clinical features and laboratory investigation of a new case with this condition, reviews the literature and discusses the syndrome with special regard to the etiology.  相似文献   
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The global spread of human immunodeficiency virus (HIV) is dependent on the ability of this virus to efficiently cross from one host to the next by traversing a mucosal membrane. Unraveling how mucosal exposure of HIV results in systemic infection is critical for the development of effective therapeutic strategies. This review focuses on understanding the immune events associated with the oral route of transmission (via breastfeeding or sexual oral intercourse), which occurs across the oral and/or gastrointestinal mucosa. Studies in both humans and simian immunodeficiency virus (SIV) monkey models have identified viral changes and immune events associated with oral HIV/SIV exposure. This review covers our current knowledge of HIV oral transmission in both infants and adults, the use of SIV models in understanding early immune events, oral immune factors that modulate HIV/SIV susceptibility (including mucosal inflammation), and interventions that may impact oral HIV transmission rates. Understanding the factors that influence oral HIV transmission will provide the foundation for developing immune therapeutic and vaccine strategies that can protect both infants and adults from oral HIV transmission.  相似文献   
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Oxidative metabolism of the human eosinophil   总被引:14,自引:1,他引:14  
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst.  相似文献   
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Obsessive–compulsive disorder (OCD) is a psychiatric illness that significantly impacts affected patients and available treatments yield suboptimal therapeutic response. Recently, the role of the gut–brain axis (GBA) in psychiatric illness has emerged as a potential target for therapeutic exploration. However, studies concerning the role of the GBA in OCD are limited. To investigate whether a naturally occurring obsessive–compulsive‐like phenotype in a rodent model, that is large nest building in deer mice, is associated with perturbations in the gut microbiome, we investigated and characterised the gut microbiota in specific‐pathogen‐free bred and housed large (LNB) and normal (NNB) nest‐building deer mice of both sexes (n = 11 per group, including three males and eight females). Following baseline characterisation of nest‐building behaviour, a single faecal sample was collected from each animal and the gut microbiota analysed. Our results reveal the overall microbial composition of LNB animals to be distinctly different compared to controls (PERMANOVA p < .05). While no genera were found to be significantly differentially abundant after correcting for multiple comparisons, the normal phenotype showed a higher loading of Prevotella and Anaeroplasma, while the OC phenotype demonstrated a higher loading of Desulfovermiculus, Aestuariispira, Peptococcus and Holdemanella (cut‐off threshold for loading at 0.2 in either the first or second component of the PCA). These findings not only provide proof‐of‐concept for continued investigation of the GBA in OCD, but also highlight a potential underlying aetiological association between alterations in the gut microbiota and the natural development of obsessive–compulsive‐like behaviours.  相似文献   
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包膜活性炭吸附血液灌流清除人血浆中毒鼠强的实验   总被引:1,自引:0,他引:1  
目的:观察包膜活性炭对血浆中毒鼠强的清除率及吸附规律。方法:实验于2004-05/2006-04在军事医学科学院毒物药物研究所国家重点实验室完成。采用包膜活性炭灌流器对毒鼠强血浆样进行血液灌流吸附,在灌流的1,2,3h分别取样,经乙酸乙酯萃取后,用气相色谱氮磷检测器法(GC/NPD)测定其含量并计算清除率。结果:活性炭对毒鼠强的吸附作用在血液灌流1h最高,灌流2h后毒鼠强质量浓度无明显变化。400,200μg/L毒鼠强血液灌流1h清除率分别为(57.83±1.85)%,(48.18±1.81)%。结论:用包膜活性炭吸附剂进行血浆的灌流吸附,能清除大部分毒物,迅速降低血浆中毒鼠强的质量浓度。  相似文献   
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Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings.  相似文献   
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